What if the Flood Maps Are Just Plain Wrong?

As Hurricane Sandy approached the Northeast coastline last year, hundreds of families felt secure that they would remain safely above the worst of it. Their confidence came from longstanding assurances that federal flood maps were correct, that their homes and businesses were officially outside the flood plains predicted for even the worst of storms.

In many cases, those maps were wrong. And as journalists from ProPublica and WNYC Radio reported on Friday, “government officials knew it.”

If these maps were decorative or meant simply to give a general idea of flood prone areas, that would be one thing. But that’s not the case. These documents were drawn up by the Federal Emergency Management Agency to help developers and homeowners determine how high to elevate structures and where to put utilities. Moreover, these maps determined whether homeowner needed to buy federal flood insurance.
Better maps cost big money, and Congress has been notoriously stingy about helping FEMA chart the places where storms and floods can bring so much destruction. In 2003, lawmakers offered only $200 million a year to remap the entire country.

With that small down payment, FEMA decided it could only afford to digitize old flood maps in many areas instead of fully updating them. Obviously, that was a mistake. Shorelines had changed since these first maps were drawn, and the agency failed to use new laser technology that could chart the landscape ten times better than the previous methods.

In New York City alone, ProPublica found that there were almost 10,000 buildings that were damaged by Sandy even though they were outside the official FEMA flood zones.

Since 2009, FEMA has been working to modernize its maps in the New York City area and a final map is not expected until 2015. Still, that is better than some other places. Residents of certain counties in New Jersey and even some in areas around New Orleans are still relying on paper maps from the 1970’s and 1980’s.

Note to members of Congress and to budget officials at FEMA: skimping on flood maps is a very costly and very dangerous business.